# US 5,332,460 A · Method of manufacturing a seal ring for magnetic fluid seal device

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- Number: US 5,332,460 A
- Document ID: US5332460A
- Status: Granted
- Kind: A
- Application number: 07/591,595
- Filed: 1990-10-02
- Granted: 1994-07-26
- Earliest claimed: 1988-08-09
- Assignees: Nippon Seiko Kabushiki Kaisha
- Inventors: Masachi Hosoya
- Web page: https://patentgrep.com/patent/US5332460A

## CPC

- B29B 13/022: {Melting the material to be shaped}
- Y10S 277/931: Seal including temperature responsive feature
- Y10T 29/49078: Laminated
- B29B: PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A seal ring for magnetic fluid seal device, comprising an annular magnet covered with heat activated resin and an annular pole piece stacked and pressed and bonded coaxially with said annular magnet at a temperature higher than heat activated temperature.

## Claims

### Claim 1

A method of manufacturing a seal ring for a magnetic fluid seal device comprising
providing an annular magnet,
applying a covering film of a heat activated resin to the magnet in a film thickness in a range of 5-30 um,
stacking the magnet coaxially between a pair of annular pole pieces, and
pressing the pole pieces against the magnet while heating the resin to a temperature at least about that at which resin in the film thereof is caused to melt and function as an adhesive for bonding the pole pieces to the magnet therewith forming a seal ring for a magnetic fluid seal device.

### Claim 2

A method of manufacturing a seal ring for a magnetic fluid seal device comprising
providing an annular magnet,
covering the magnet with a heat activated resin, by dissolving the resin in a solvent having a boiling point temperature of less than 120.degree. C. spraying the dissolved resin onto the magnet and heating the sprayed magnet, at a temperature of approximately 80.degree. C. for a time sufficient to vaporize the solvent,
providing a pair of annular pole pieces,
coaxially stacking the magnet between the pole pieces, and
pressing the pole pieces against the magnet while heating the same at a temperature in excess of the activation temperature of the heat activated resin to bond the pole pieces to the magnet thereby forming a seal ring for a magnetic fluid seal device.